Surgical assembly and method for repairing depression fractures

ABSTRACT

A surgical assembly according to an exemplary aspect of the present disclosure includes, among other things, a cannula and an obturator receivable through the cannula and configured to manipulate a depressed bone fragment associated with a depression fracture.

BACKGROUND

This disclosure relates to a surgical assembly and method for reducingdepression fractures.

Prolonged periods of high force impact and stress during sportingactivities can result in depression fractures in the articulatingsurfaces of joints. Collapsed bone fragments associated with thedepression fracture can depress into softer cancellous bone locatedbeneath relatively hard cortical bone. The collapsed bone fragments mustbe returned to their original anatomical position to stabilize the jointand minimize the risk of post traumatic osteoarthritis.

SUMMARY

A surgical assembly according to an exemplary aspect of the presentdisclosure includes, among other things, a cannula and an obturatorreceivable through the cannula and configured to manipulate a depressedbone fragment associated with a depression fracture.

In a further non-limiting embodiment of the foregoing surgical assembly,the obturator includes a blunt tip that extends beyond a distal end ofthe cannula.

In a further non-limiting embodiment of either of the foregoing surgicalassemblies, the blunt tip is rounded.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the blunt tip and the distal end are curved and extend alongan axis that is transverse to a longitudinal axis of the surgicalassembly.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the cannula includes a tube that extends between a fittingand a distal end.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the tube includes a passage that extends between the fittingand the distal end.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, a plurality of openings are formed through the tube at thedistal end.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the obturator includes a shaft that extends between a handleand a blunt tip.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the handle includes a fitting and a grip that extends fromthe fitting.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the obturator is removable from the cannula.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the assembly includes a delivery device for injecting arepair material through the cannula after removing the obturator.

In a further non-limiting embodiment of any of the foregoing surgicalassemblies, the cannula includes a first fitting and the obturatorincludes a second fitting configured to engage the first fitting toconnect the obturator to the cannula.

A surgical method according to another exemplary aspect of the presentdisclosure includes, among other things, accessing a depressed bonefragment of a depression fracture with a surgical assembly. The surgicalassembly includes a cannula and an obturator receivable through thecannula. The method further includes positioning the depressed bonefragment toward its original anatomical position using a blunt tip ofthe obturator.

In a further non-limiting embodiment of the foregoing surgical method,the accessing step includes locating the blunt tip of the obturatorbeneath the depressed bone fragment.

In a further non-limiting embodiment of either of the foregoing surgicalmethods, the locating step includes positioning the blunt tip such thatit is generally perpendicular to the depressed bone fragment.

In a further non-limiting embodiment of any of the foregoing surgicalmethods, the method includes, prior to the accessing step, forming apilot hole through cortical bone that is located inferior to thedepression fracture.

In a further non-limiting embodiment of any of the foregoing surgicalmethods, the method includes, subsequent to the positioning step,removing the obturator from the cannula.

Nom In a further non-limiting embodiment of any of the foregoingsurgical methods, the method includes injecting a repair materialthrough the cannula after the removing step.

In a further non-limiting embodiment of any of the foregoing surgicalmethods, the blunt tip extends past a distal end of the cannula.

In a further non-limiting embodiment of any of the foregoing surgicalmethods, the positioning step includes raising the depressed bonefragment toward the original anatomical position.

The embodiments, examples and alternatives of the preceding paragraphs,the claims, or the following description and drawings, including any oftheir various aspects or respective individual features, may be takenindependently or in any combination. Features described in connectionwith one embodiment are applicable to all embodiments, unless suchfeatures are incompatible.

The various features and advantages of this disclosure will becomeapparent to those skilled in the art from the following detaileddescription. The drawings that accompany the detailed description can bebriefly described as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a surgical assembly according to a first embodimentof this disclosure.

FIG. 2 illustrates a blown up view of region R1 of FIG. 1.

FIG. 3 illustrates a cannula of the surgical assembly of FIG. 1.

FIG. 4 illustrates an obturator of the surgical assembly of FIG. 1.

FIG. 5 illustrates portions of a surgical assembly according to anotherembodiment of this disclosure.

FIGS. 6, 7, 8, 9 and 10 schematically illustrate a method of reducing adepression fracture.

DETAILED DESCRIPTION

This disclosure details surgical assemblies and associated methods forreducing a depression fracture of a musculoskeletal joint. The surgicalassembly includes a cannula and an obturator receivable through thecannula and configured to position a depressed bone fragment. Thedepressed bone fragment may be accessed and elevated to its originalanatomical position using the surgical assembly. These and otherfeatures are described in greater detail on the following paragraphs ofthis detailed description.

FIGS. 1 and 2 illustrate a surgical assembly 10 for reducing adepression fracture. The surgical assembly 10 includes a cannula 12 andan obturator 14 removably received within the cannula 12. A passage 20may extend entirely through the cannula 12. In other words, the cannula12 is cannulated. The obturator 14 is insertable through the passage 20to access depressed bone fragments associated with a depressionfracture. In one non-limiting embodiment, the obturator 14 is removablyattachable to the cannula 12. For example, the cannula 12 and obturator14 may be connected together using a luer connection. Other connections;however, are also contemplated within the scope of this disclosure.

The obturator 14 may include a blunt tip 16 that extends past a distalend 18 of the cannula 12. The blunt tip 16 is configured to positiondepressed bone fragment(s) associated with a depression fracture. In anembodiment, the blunt tip 16 is configured as a non-traumatic tipdesigned to avoid damaging the depressed bone fragments.

Referring primarily to FIG. 2, which is a blown up view of region R1 ofFIG. 1, both the distal end 18 of the cannula 12 and the blunt tip 16 ofthe obturator 14 may be curved. In an embodiment, the distal end 18 andthe blunt tip 16 are both curved such that they extend at a transverseangle α relative to a longitudinal axis A of the surgical assembly 10.The actual angle of the curvature may vary depending on the joint beingrepaired, among other factors. The distal end 18 of the cannula 12 andthe blunt tip 16 of the obturator 14 may be pre-bent or can be bent inthe operating room just prior to performing a depression fracturereduction surgery.

FIG. 3, with continued reference to FIGS. 1 and 2, further illustratesthe cannula 12 of the surgical assembly 10. The cannula 12 includes atube 15 that extends along the longitudinal axis A between a fitting 22,disposed proximally, and the distal end 18. The distal end 18 of thecannula 12 may include a plurality of openings 24, or fenestrations,formed through the tube 15. The plurality of openings 24 are in fluidcommunication with the passage 20 that extends through the tube 15.

The fitting 22 is configured for connection to the obturator 14. In onenon-limiting embodiment, the fitting 22 is a male luer lock fitting thatmay be rotatably received within a female luer lock fitting of theobturator 14. Other fitting configurations are also contemplated,including an embodiment in which the fitting 22 of the cannula 12provides the female connection and the obturator 14 provides the maleconnection. In yet another embodiment, the fitting 22 includes a grip 17for gripping the cannula 12 (see, for example, the embodiment of FIG.5).

In one non-limiting embodiment, the cannula 12 is made of a metallicmaterial, such as stainless steel. In another embodiment, the cannula 12may be made of a non-metallic material, such as a plastic. The tube 15and the fitting 22 of the cannula 12 may be made of either similar ordissimilar materials.

FIG. 4, with continued reference to FIGS. 1 and 2, further illustratesthe obturator 14 of the surgical assembly 10. The obturator 14 includesa shaft 25 that extends along the longitudinal axis A between a handle26 and the blunt tip 16. In one non-limiting embodiment, the blunt tip16 is rounded. However, other non-traumatic shapes are also contemplatedwithin the scope of this disclosure.

The handle 26 may include any size, shape and/or configuration. In otherwords, the handle 26 is not limited to the specific configurations shownin FIG. 4 or FIG. 5, which illustrate two non-limiting handleconfigurations. The handle 26 may include a fitting 28 and a grip 30.The fitting 28 is adapted to connect to the fitting 22 of the cannula 12(see FIGS. 1 and 5) and the grip 30 is configured for gripping thesurgical assembly 10.

In one non-limiting embodiment, the obturator 14 is made of a metallicmaterial, such as stainless steel. Other metallic materials may also besuitable. The shaft 25 and the fitting 28 of the obturator 14 may bemade of similar or dissimilar materials.

FIGS. 6-10, with continued reference to FIGS. 1-5, schematicallyillustrate a method for reducing a depression fracture 32 of a joint 34.In one non-limiting embodiment, the joint 34 is a knee joint thatincludes a femur 36 and a tibia 38 and the depression fracture 32 is adepression fracture of the tibial plateau 40. However, the depressionfracture 32 could alternatively be a fracture associated with a HillSachs lesion, the calcaneus, the distal radius, or any other bone orjoint. In this disclosure, the phrase “depression fracture” indicates afracture in which one or more bone fragments 45 depress into the softercancellous bone 42 located beneath relatively hard cortical bone 44. Thedepressed bone fragment(s) 45 must be returned to their originalanatomical position to stabilize the joint 34. The method shown in FIGS.6-10 may be performed as either an arthroscopic method or an openmethod.

Referring first to FIG. 6, a pilot hole 46 is formed through thecortical bone 44. The pilot hole 46 provides an opening through whichthe depressed bone fragment(s) 45 associated with the depressionfracture 32 may be accessed using the surgical assembly 10. In onenon-limiting embodiment, the pilot hole 46 is formed at approximately a45° angle at a location of the cortical bone 44 that is inferior to(i.e., below) the depression fracture 32. In another embodiment, thepilot hole 46 is formed on the same side of the joint 34 as thedepression fracture 32. For example, the pilot hole 46 is formed on themedial side of the tibia 38 if the depression fracture 32 is locatedmedially and is formed on the lateral side of the tibia 38 if thedepression fracture 32 is located laterally. The location of the pilothole 46 may be chosen with the aid of fluoroscopic imaging techniquesthat provide a real-time understanding of the positioning of thedepressed bone fragments 45 and the various other structures thatmake-up the joint 34.

FIG. 7 schematically illustrates guidance of the surgical assembly 10through the pilot hole 46 for accessing the depressed bone fragment(s)45. In an embodiment, the tube 15 of the cannula 12 includes an outerdiameter that is smaller than the pilot hole 46 to ease insertion of thesurgical assembly 10 into the joint 34. The handle 26 of the obturator14 and/or the grip 17 of the cannula 12 may be used to guide thesurgical assembly 10 to a desired positioning beneath the depressed bonefragment(s) 45. The handle 26 and/or the grip 17 also provide sufficientleverage for inserting and guiding the surgical assembly 10 through thecancellous bone 42 to access the depression fracture 32.

After a desired positioning is achieved, the surgical assembly 10 may beused to manipulate the depressed bone fragment(s) 45 back to an originalanatomical position. For example, as best illustrated in FIG. 8, theblunt tip 16 of the obturator 14 may be used to reduce the depressedbone fragment(s) 45 as close as is possible back to an originalanatomical position 50 (shown schematically in dashed lines in FIG. 8).The handle 26 of the obturator 14 and/or the grip 17 of the cannula 12provide sufficient leverage for lifting the depressed bone fragments 45of the depression fracture 32. In one non-limiting embodiment, by virtueof the curved nature of the distal end 18 of the cannula 12 and theblunt tip 16 of the obturator 14, the blunt tip 16 may approach thedepression fracture 32 at a perpendicular angle relative to thedepressed bone fragments 45. Approaching the bone fragments 45 at suchan angle simplifies manipulation of the depressed bone fragments 45 forimproved approximation back toward the original anatomical position 50.

As shown in FIG. 9, the obturator 14 may be disconnected from thecannula 12 and then removed from the joint 34 after reducing thedepressed bone fragments 45. The cannula 12, however, may be left insidethe joint 34 for preforming additional surgical steps.

For example, as shown in FIG. 10, a repair material 60 may be injectedinto the joint 34 to backfill the hollow area immediately beneath thebone fragments 45 of the depression fracture 32, which have not beenlifted back toward their original anatomical position. The repairmaterial 60 is delivered using a delivery device 62 that can be insertedinto and through the cannula 12. The delivery device 62 may include asyringe and tube, in one non-limiting embodiment. During injection, therepair material 60 may flow through the passage 20 of the cannula 12 andthen out of the openings 24 as well as the open distal end 18 (see FIG.3).

The repair material 60 may include resorbable or non-resorbable bonecement, a bone graft, a bone plug allograft or an autologous material.These, of course, are intended as non-limiting examples of suitablematerials. The cannula 12 is removed from the joint 34 to complete thedepression fracture reduction procedure.

Although the different non-limiting embodiments are illustrated ashaving specific components, the embodiments of this disclosure are notlimited to those particular combinations. It is possible to use some ofthe components or features from any of the non-limiting embodiments incombination with features or components from any of the othernon-limiting embodiments.

It should be understood that like reference numerals identifycorresponding or similar elements throughout the several drawings. Itshould also be understood that although a particular componentarrangement is disclosed and illustrated in these exemplary embodiments,other arrangements could also benefit from the teachings of thisdisclosure.

The foregoing description shall be interpreted as illustrative and notin any limiting sense. A worker of ordinary skill in the art wouldunderstand that certain modifications could come within the scope ofthis disclosure. For these reasons, the following claims should bestudied to determine the true scope and content of this disclosure.

What is claimed is:
 1. A surgical assembly, comprising: a cannula; andan obturator receivable through said cannula and configured tomanipulate a depressed bone fragment associated with a depressionfracture.
 2. The surgical assembly as recited in claim 1, wherein saidobturator includes a blunt tip that extends beyond a distal end of saidcannula.
 3. The surgical assembly as recited in claim 2, wherein saidblunt tip is rounded.
 4. The surgical assembly as recited in claim 2,wherein said blunt tip and said distal end are curved and extend alongan axis that is transverse to a longitudinal axis of said surgicalassembly.
 5. The surgical assembly as recited in claim 1, wherein saidcannula includes a tube that extends between a fitting and a distal end.6. The surgical assembly as recited in claim 5, wherein said tubeincludes a passage that extends between said fitting and said distalend.
 7. The surgical assembly as recited in claim 5, comprising aplurality of openings formed through said tube at said distal end. 8.The surgical assembly as recited in claim 1, wherein said obturatorincludes a shaft that extends between a handle and a blunt tip.
 9. Thesurgical assembly as recited in claim 8, wherein said handle includes afitting and a grip that extends from said fitting.
 10. The surgicalassembly as recited in claim 1, wherein said obturator is removable fromsaid cannula.
 11. The surgical assembly as recited in claim 10,comprising a delivery device for injecting a repair material throughsaid cannula after removing said obturator.
 12. The surgical assembly asrecited in claim 1, wherein said cannula includes a first fitting andsaid obturator includes a second fitting configured to engage said firstfitting to connect said obturator to said cannula.
 13. A surgicalmethod, comprising: accessing a depressed bone fragment of a depressionfracture with a surgical assembly, the surgical assembly including acannula and an obturator receivable through the cannula; and positioningthe depressed bone fragment toward its original anatomical positionusing a blunt tip of the obturator.
 14. The surgical method as recitedin claim 13, wherein the accessing step includes locating the blunt tipof the obturator beneath the depressed bone fragment.
 15. The surgicalmethod as recited in claim 14, wherein the locating step includespositioning the blunt tip such that it is generally perpendicular to thedepressed bone fragment.
 16. The surgical method as recited in claim 13,comprising, prior to the accessing step, forming a pilot hole throughcortical bone that is located inferior to the depression fracture. 17.The surgical method as recited in claim 13, comprising, subsequent tothe positioning step, removing the obturator from the cannula.
 18. Thesurgical method as recited in claim 17, comprising injecting a repairmaterial through the cannula after the removing step.
 19. The surgicalmethod as recited in claim 13, wherein the blunt tip extends past adistal end of the cannula.
 20. The surgical method as recited in claim13, wherein the positioning step includes raising the depressed bonefragment toward the original anatomical position.